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AMC Record Player has crazy loud HUMM

That’s what I’m starting to think. I bought a new cartridge when I first got it and it looked way better than the old one. Although im wondering if the socket could cause this possibly with corrosion?
 

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ryan lambert said:
That’s what I’m starting to think. I bought a new cartridge when I first got it and it looked way better than the old one. Although im wondering if the socket could cause this possibly with corrosion?
Click to expand...

Yes, clean all sockets, plugs, jacks, all connections --- with DeOxit D100. Work the connections a few times, to get them nice and clean.

https://www.amazon.com/CAIG-LABORATORIES-D100L-25C-Contact-Cleaner/dp/B0000YH6F8/ref=sr_1_2?crid=3GDUJ3IZG6GU7&keywords=deoxit+d100&qid=1684851682&sprefix=deoxit+d100,aps,145&sr=8-2
 
change the other caps while you're in there and confirm the B+ is actually where it should be. A common fail mode is the rectifier becomes overly lossy and the voltage ends up very low.
 
ryan lambert said:
That’s what I’m starting to think. I bought a new cartridge when I first got it and it looked way better than the old one. Although im wondering if the socket could cause this possibly with corrosion?
Click to expand...

The new cartridge might have lower output than the original. The old high output cartridges are not made anymore, so people are forced to substitute lower output replacements.

Just as an experiment try changing R5 and R6 (22k) to 100k. This should increase gain and give you more satisfying volume.
 
ryan lambert said:
What would be the best way to check the B+ voltage?
Click to expand...

across the filter caps would be easiest. They go from + to -. Schematic doesn't say but taking some guesses, about 130vdc, 100, and 70vdc wouldn't be completely goofy. The one right off the rectifier would usually be the tell, if its under 100v, something is probably wrong with the rectifier, or the resistor wired to the rectifier is way high in value.
 
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